The Ministry of Justice will begin to end the lease on HMP Dartmoor.
The site has a ten-year lease notice period but the MoJ said the age and limitations of the prison mean that it does not have a long-term future in a modern, cost-effective prison system.
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Sunshine all day tomorrow and warm week ahead
Lovely and warm with highs of 23 and 24 degrees. Hottest on Wednesday.
Searches are being carried out in Nunney in Somerset for 86-year-old Kenneth Scotcher.